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This study investigated the effect of ultrasonic activation of intracanal‐heated sodium hypochlorite (NaOCl) on its dentinal tubular penetration and root canal cleanliness in vitro. In experiment 1, mandibular premolars were randomly allocated to three groups (n = 8): group A, ultrasonic activation; group B, ultrasonic activation of intracanal‐heated NaOCl and group C, syringe‐and‐needle irrigation. Penetration of the fluorescent‐labelled NaOCl was investigated using light microscopy. In experiment 2, mandibular premolars were randomly allocated to group B or C (n = 10), for histological analysis of the remaining pulp tissue and debris. Data were statistically analysed using Kruskal–Wallis and Mann–Whitney tests (P = 0.05). The highest penetration of NaOCl was observed in group B, followed by group A (P < 0.05). Group B showed significantly less amount of debris than group C (P < 0.05). Dentinal tubule penetration of NaOCl and root canal cleanliness were significantly improved by ultrasonic activation of intracanal‐heated NaOCl.  相似文献   
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Objective : To evaluate if tbere was periodicity in the manifestations of gastrointestinal bleeding (hemateme-sis and melena). Method : This is a multicenter prospective study carried out in the Endoscopy Units of eight hospitals. At the time of the emergency endoscopy, the following data were collected: age, sex, endoscopic diagnosis, solar hour of the first hematemesis (vomiting of bright red or tarry black material) and of the first melena (black or bloody soft stools), and any drugs taken during the week before the bleeding episode, regardless of the dose. Results : 806 patients were studied. Bleeding was from peptic ulcer in 405 patients (50%), from esophageal varices in 197 (24%), and from other sources in the remainder. Analysis using single cosinor statistics showed a nonrandom distribution in bleeding from peptic ulcer, whether presenting first with hematemesis (p = 0.02) or melena (p = 0.03). There were two peaks at 6:45 AM and 6:45 PM for hemate-mesis and at 7:25 AM and 7:25 PM for melena, representing a biphasic diurnal (ultradian) rhythm. Conclusions : This study shows that bleeding due to peptic ulcer has a biphasic diurnal periodicity. 1 his has potential importance for the pathogenesis of bleeding, for the management of gastrointestinal hemorrhage and the administration of drugs known to cause peptic ulcer bleeding.  相似文献   
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BACKGROUND: Whether to include only those patients who have not had prior hypertension treatment in clinical trials of left ventricular (LV) mass reduction is controversial. Accordingly, our aim was to study the relationship between prior treatment and both baseline and 1-year echocardiographic LV mass in subjects enrolled in the Losartan Intervention For Endpoint reduction (LIFE) study. METHODS: We studied clinical and baseline echocardiographic data on 960 patients with electrocardiographically confirmed left ventricular hypertrophy enrolled in the electrocardiographic substudy of the LIFE study, 847 of whom had LV mass remeasured after 1 year of blinded treatment. The majority (75%) of these patients had prior medical treatment for hypertension. RESULTS: In multivariable regression analysis, controlling for age, sex, blood pressure (BP), body mass index, and indices of pump and myocardial function, prior antihypertensive treatment was not associated with either greater LV mass or relative wall thickness on the baseline study. Moreover, there was no significant difference between the 637 subjects who were previously treated and the 210 who were not treated with regard to the mean reduction in systolic or diastolic pressures (-25 +/- 17 v -24 +/- -16 and -13 +/- 9 mm Hg v -12 +/- 9 mm Hg), LV mass (-27 +/- 38 v -29 +/- 34 g), or LV mass/body surface area (-14 +/- 20 v -15 +/- 18 g/m(2)), all P >.05. CONCLUSIONS: Prior treatment is not associated with either greater LV mass or greater relative wall thickness when age, body mass index, sex, systolic BP, heart rate, or indices of LV volume load and systolic function are taken into account. In addition, prior treatment is not associated with lesser degrees of LV mass reduction. For design of future clinical trials, restriction of inclusion criteria to only previously untreated patients does not appear to be necessary when the selection criterion is electrocardiographically determined left ventricular hypertrophy.  相似文献   
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Background

Contrast-enhanced intra-operative ultrasound (CE-IOUS) for colorectal liver metastases (CLMs) has become a part of clinical practice. Whether it should be selectively or routinely applied remains unclear. The aim of this study was to define criteria for the use of CE-IOUS.

Methods

One-hundred and twenty-seven patients underwent a hepatectomy for CLMs using IOUS and CE-IOUS. All patients underwent computed tomography (CT) and/or magnetic resonance imaging (MRI) within 2 weeks prior to surgery. The reference was histology, and imaging at 6 months after surgery. Univariate and multivariate analyses were performed. Statistical significance was set at P = 0.05.

Results

Using IOUS an additional 172 lesions in 51 patients were found. CE-IOUS found 14 additional lesions in 6 patients. Seventy-eight CLMs in 38 patients appeared within 6 months after surgery. The sensitivity, specificity, positive- and negative-predictive value were 63%, 98%, 100% and 27% for pre-operative imaging, 87%, 100%, 100% and 52% for IOUS, and 89%, 100%, 100% and 56% for IOUS+CE-IOUS, respectively. CE-IOUS allowed better tumour margin definition in 23 patients (18%), thus assisting resection. Analyses indicated that the presence of multiple (P = 0.014), and isoechoic CLMs (P = 0.049) were independently correlated with new findings at CE-IOUS.

Conclusions

Compared with IOUS, CE-IOUS improved detection and resection guidance. These additions are significant and demand its use in cases with multiple and isoechoic CLMs.  相似文献   
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